Neurovascular free-muscle transfer for the treatment of established facial paralysis following ablative surgery in the parotid region

Neurovascular free-muscle transfer for facial reanimation was performed as a secondary reconstructive procedure for 45 patients with facial paralysis resulting from ablative surgery in the parotid region. This intervention differs from neurovascular free-muscle transfer for treatment of established facial paralysis resulting from conditions such as congenital dysfunction, unresolved Bell palsy, Hunt syndrome, or intracranial morbidity, with difficulties including selection of recipient vessels and nerves, and requirements for soft-tissue augmentation. This article describes the authors' operative procedure for neurovascular free-muscle transfer after ablative surgery in the parotid region. Gracilis muscle (n = 24) or latissimus dorsi muscle (n = 21) was used for transfer. With gracilis transfer, recipient vessels comprised the superficial temporal vessels in 12 patients and the facial vessels in 12. For latissimus dorsi transfer, recipient vessels comprised the facial vessels in 16 patients and the superior thyroid artery and superior thyroid or internal jugular vein in four. Facial vessels on the contralateral side were used with interpositional graft of radial vessels in the remaining patient with latissimus dorsi transfer. Cross-face nerve grafting was performed before muscle transfer in 22 patients undergoing gracilis transfer. In the remaining two gracilis patients, the ipsilateral facial nerve stump was used as the primary recipient nerve. Dermal fat flap overlying the gracilis muscle was used for cheek augmentation in one patient. In the other 23 patients, only the gracilis muscle was used. With latissimus dorsi transfer, the ipsilateral facial nerve stump was used as the recipient nerve in three patients, and a cross-face nerve graft was selected as the recipient nerve in six. The contralateral facial nerve was selected as the recipient nerve in 12 patients, and a thoracodorsal nerve from the latissimus dorsi muscle segment was crossed through the upper lip to the primary recipient branches. A soft-tissue flap was transferred simultaneously with the latissimus muscle segment in three patients. Contraction of grafted muscle was not observed in two patients with gracilis transfer and in three patients with latissimus dorsi transfer. In one patient with gracilis transfer and one patient with latissimus dorsi transfer, acquired muscle contraction was excessive, resulting in unnatural smile animation. The recipient nerves for both of these patients were the ipsilateral facial nerve stumps, which were dissected by opening the facial nerve canal in the mastoid process. From the standpoint of operative technique, the one-stage transfer for latissimus dorsi muscle appears superior. Namely, a combined soft-tissue flap can provide sufficient augmentation for depression of the parotid region following wide resection. A long vascular stalk of thoracodorsal vessels is also useful for anastomosis, with recipient vessels available after extensive ablation and neck dissection.     

The serratus anterior subslip: anatomy and implications for facial and hand reanimation

The ideal donor muscle for facial and hand reanimation has yet to be found. Donor muscles commonly used today, such as the gracilis and pectoralis minor, are limited by bulkiness and the number of force vectors they can provide. In the authors' study of 50 fresh cadaver serratus anterior muscles, they further describe neurovascular anatomy of the muscle slip (i.e., the portion of the muscle that inserts on a rib) and subslip (superficial or deep subdivision of the slip after division along a loose areolar plane). All 260 slips could be separated into a deep and a superficial subslip, yielding a total of 520 subslips. A branch of the serratus artery (a terminal branch of the thoracodorsal artery serving the lower five to seven slips of the muscle) and a branch of the long thoracic nerve were identified for each of these. Deep subslips were thinner than superficial subslips, both at the origin of the slip on the rib periosteum (2.4 mm versus 3.0 mm, p < 0.0001) and centrally at the serratus artery (3.3 mm versus 4.0 mm, p < 0.0001). In addition, the subslips of the most inferior slip were thinner than those of more superior slips, both at the origin of the slip (2.3 mm versus 2.8 mm, p < 0.0001) and at the serratus artery (3.0 mm versus 3.8 mm, p < 0.0001). Fine anastomosing vessels were present between the slips and the subslips. The average number of anastomosing vessels present between adjacent slips was 1.7, and 2.1 anastomosing vessels were present between the subslips of a given slip. Given the thinness of these vessels (all less than 0.2 mm) compared with those of the vascular pedicle of the subslip (mean, 0.7 mm; all greater than 0.4 mm), the authors believe these can be safely divided without compromising subslip vascularity. After division of these vessels, a mean length of 9.6 +/- 1.5 cm is available to allow independent orientation of each subslip. When the serratus muscle flap is separated into its component subslips, a maximum of 10 possible force vectors may be transferred on a single vascular pedicle. Subslips are significantly thinner than donor muscles commonly used today. These two advantages offer the potential for significant functional and aesthetic improvement when the serratus anterior muscle flap is used for face and hand reanimation. Mimetic muscles such as the orbicularis oculi and orbicularis oris could possibly be reconstructed in their proper anatomical positions.     

Neurovascular free-muscle transfer to treat facial paralysis associated with hemifacial microsomia

Despite the wide spectrum of hemifacial microsomia manifestations, treatment mainly focuses on mandible and ear abnormalities, rather than on facial paralysis. In fact, the surgical treatment of facial paralysis associated with hemifacial microsomia is quite underdeveloped, because the degree of paralysis is frequently incomplete or partial. Timing and type of surgery are also difficult to determine. Neurovascular free-muscle transfer is now a standard procedure for the dynamic smile reconstruction of longstanding facial paralysis. This type of strategy has considerable potential in the treatment of facial paralysis in patients with hemifacial microsomia. We present here our experience with neurovascular free-muscle transfer for smile reconstruction in eight patients with facial paralysis associated with hemifacial microsomia. The age of the patients at the time of surgery ranged from 7 to 28 years old, (average, 13.9 years). Six were male patients and two were female patients. The two-stage method combining gracilis muscle transfer with cross-face nerve grafting was performed in three patients, whereas the one-stage transfer of the latissimus dorsi muscle was performed in five. To construct a natural or near-natural smile, the muscles were transferred into the paralyzed cheek in all except one patient, in whom the latissimus dorsi muscle was transferred into the sublabial area to reconstruct a paralyzed lower lip. A dermal flap segment vascularized with perforating vessels from the latissimus dorsi muscle was simultaneously inserted into the underdeveloped cheek for soft-tissue augmentation in this patient. Muscle contraction was evident in all patients between 4 and 8 months after muscle transfer. Our present series revealed that neurovascular free-muscle transfer is a good option not only for smile reconstruction but also for restoration of the facial contours of patients with hemifacial microsomia. Compared with the two-stage method combining gracilis muscle transfer with cross-face nerve grafting, the one-stage method using the latissimus dorsi muscle has some advantages, including a one-stage operation, a shorter recovery period, and the absence of sequelae that occur after harvesting a sural nerve.     

Results of management of facial palsy with microvascular free-muscle transfer

This paper reports our experience in facial reanimation using free innervated muscle transfer in 69 patients with long-term facial palsy. The majority of patients were treated in two stages with cross-facial nerve graft as the first stage and microvascular muscle transfer at the second stage. The gracilis muscle was used in 62 patients. A system of grading results has been utilized in the long-term evaluation. The overall final result was excellent or good in 51 percent of 47 patients who were available for follow-up. Although the results are not completely satisfactory, they justify the use of this approach to a difficult clinical problem. The results are improving as technical modifications to the procedure have evolved. The gracilis muscle is a reliable free transfer with internal anatomy conductive to use for reanimation of the paralyzed face. This type of transfer, in our experience, has proved superior to nonmicrosurgical methods for treatment of complete and severe incomplete facial palsy. The seventh cranial nerve is used in the innervation of the transferred muscle, the ipsilateral being preferable if available. The authors believe that use of the same cranial nerve is superior to methods that involve other cranial nerves, where spontaneity is often not achieved.     

The computer synthesis of expressive faces.

This paper presents a methodology for the computer synthesis of realistic faces capable of expressive articulations. A sophisticated three-dimensional model of the human face is developed that incorporates a physical model of facial tissue with an anatomical model of facial muscles. The tissue and muscle models are generic, in that their structures are independent of specific facial geometries. To synthesize specific faces, these models are automatically mapped onto geometrically accurate polygonal facial representations constructed by photogrammetry of stereo facial images or by non-uniform meshing of detailed facial topographies acquired by using range sensors. The methodology offers superior realism by utilizing physical modelling to emulate complex tissue deformations in response to coordinated facial muscle activity. To provide realistic muscle actions to the face model, a performance driven animation technique is developed which estimates the dynamic contractions of a performer's facial muscles from video imagery.     

Neurovascular musculus obliquus internus abdominis flap free transfer for facial reanimation in a single stage

A study of the anatomy and transplantation of the musculus obliquus internus abdominis with a neurovascular pedicle transfer for facial reanimation in one stage is presented. Eleven adult cadavers (22 face sides) were dissected to observe the shape, thickness, innervation, and blood supply of the musculus obliquus internus abdominis. The blood supply of this muscle primarily comes from the musculus obliquus internus abdominis branch of the deep circumflex iliac artery (diameter, 1.3 +/- 0.2 mm), but it can also come from the eleventh intercostal artery (diameter, 1.14 +/- 0.3 mm) and the infracostal artery (diameter, 1.5 +/- 0.2 mm). The branch of the deep circumflex iliac artery and its vena comitans, or the infracostal artery and its vena comitans, could be anastomosed for muscle transplantation. The innervation of the musculus obliquus internus abdominis comes from the tenth and eleventh intercostal nerves (length, 12.7 +/- 1.5 cm) and the infracostal nerve (length, 12.9 +/- 1.3 cm). The eleventh intercostal nerve and the infracostal nerve were selected for anastomosis of muscle transplantation. From November of 1995 to November of 1999, 14 patients with long established facial paralysis were treated with transplantation of a musculus obliquus internus abdominis flap in one stage and were followed for 10 months to 6 years. In 13 patients, the dynamic functions of the transplanted muscles were restored, the obliqueness of the mouth and philtrum while static was corrected, and the facial muscle activities while smiling were harmonized. The eyelids of the paralyzed side could be closed postoperatively, indicating that the function of the orbicularis oculi of the paralyzed side was restored. The single-stage transplantation of a free musculus obliquus internus abdominis flap with one vascular, multi-nerve pedicle is a new method for facial reanimation in the treatment of long established facial paralysis. Because of the simplicity of the procedure and the completeness of the functional reanimation of the paralyzed facial muscles, compared with the results of other free muscle flap transfers, it is an ideal procedure for facial reanimation.     

Facial animation in children with Möbius syndrome after segmental gracilis muscle transplant

M?bius syndrome is a complex congenital anomaly involving multiple cranial nerves, including the abducens (VI) and facial (II) nerves, and often associated with limb anomalies. Muscle transplantation has been used to address the lack of facial animation, lack of lower lip support, and speech difficulties these patients experience. The purpose of this study was to investigate the results of bilateral, segmental gracilis muscle transplantation to the face using the facial vessels for revascularization and the motor nerve to the masseter for reinnervation. The outcome of the two-stage procedure was assessed in 10 consecutive children with M?bius syndrome by direct interview, speech assessment, and oral commissure movement. Preoperative data were collected from direct questioning, viewing of preoperative videotapes, notes from prior medical evaluations, and rehabilitation medicine and speech pathology assessments. All of the patients developed reinnervation and muscle movement. The children who described self-esteem to be an issue preoperatively reported a significant posttransplant improvement. The muscle transplants produced a smile with an average commissure excursion of 1.37 cm. The frequency and severity of drooling and drinking difficulties decreased postoperatively in the seven symptomatic children. Speech difficulties improved in all children. Specifically, of the six children with bilabial incompetence, three received complete correction and three had significant improvement. Despite the length and complexity of these procedures, complications were minimal. Muscle transplantation had positive effects in all problematic areas, with a high degree of patient satisfaction and improvement in drooling, drinking, speech, and facial animation. The surgical technique is described in detail and the advantages over regional muscle transfers are outlined. Segmental gracilis muscle transplantation innervated by the motor nerve to the masseter is an effective method of treating patients with M?bius syndrome.     

Photogrammetry of the muscles of facial expression

The present study has attempted to determine the volume, square measure as well as length, width and thickness of the individual muscles of facial expression by photogrammetry. 15 fresh male head specimens were employed for a careful dissection of muscle layers. The volume was measured using the immersion procedure. The mean values of each parameter together with the standard deviation were summarized. The results suggest that this novelty in the representation of the mimetic muscles will facilitate the planning of corrective interventions in plastic surgery. Moreover, photogrammetry offers additional information on the required size and measurements of donor muscles.     

Forearm compartment syndrome: anatomical analysis of surgical approaches to the deep space

Forearm compartment syndrome is a surgical emergency that usually requires release of the superficial muscle compartments. In some clinical situations it is imperative to also explore the deep muscle compartments. There are no anatomical guides for surgical exploration of the deep compartments that would minimize collateral damage to surrounding vessels, nerves, and muscles. Surgical injury in the setting of ischemia, especially vascular injury, compounds the tissue damage that has already occurred. The authors evaluated four surgical approaches (three volar and one dorsal) to the deep forearm by performing detailed anatomical dissections on 10 embalmed and plastinated cadavers. They used a scoring system to rate the approaches for their ability to visualize the deep space without causing iatrogenic injury to superficial muscles, arteries, and nerves. In the volar forearm, an ulnar approach to the deep space is simple, causes the least iatrogenic surgical injury, and provides access to the deep volar forearm structures. The plane of dissection is between the flexor carpi ulnaris and the flexor digitorum superficialis. Dividing one or two distal segmental branches of the ulnar artery to the distal flexor digitorum superficialis exposes the pronator quadratus. Lifting the ulnar neurovascular bundle with the flexor digitorum superficialis in the middle third of the forearm exposes the flexor digitorum profundus and the flexor pollicis longus. This approach to the deep space requires no sharp dissection. In the dorsal forearm, a midline approach between the extensor digitorum communis and the extensor carpi radialis brevis is simple and safe.     

The pedicled transposition of the digastric and stylohyoid muscles in the treatment of velopharyngeal incompetence. Anatomic basis and clinical application]

The anatomical basis for the application of neurovascular pedicled muscle transfers of the digastric and stylohyoid muscles in the treatment of velopharynx incompetence is described. The fact that the neurovascular pedicle is located in the cranial third of the muscle bellies provides the safety of the operative procedure. The muscles have to be dissected with respect to that. The direction in which the transferred muscles pull is described. The muscle transposition is combined with the classic Wardill-Kilner operation to lengthen the soft palate. The transferred muscles have to avoid scar contraction and shortening of the soft palate and to gain a muscular function of the soft palate. The clinical use is justified in rare cases as demonstrated in one case.     

Sensory restoration of the skin graft on a free muscle flap: experimental rabbit study.

Transplantation of a muscle flap with free skin graft for wound coverage is a common procedure in reconstructive microsurgery. However, the grafted skin has little or no sensation. Restoration of the sensibility of the grafted skin on the transferred muscle is critically important, especially in palmar hand, plantar foot, heel, and oral cavity reconstruction. The purpose of this study was to investigate the possibility of sensory restoration of the grafted skin on a trimmed muscle surface that has been sensory neurotized after sensory nerve-to-motor nerve transfer, using the rabbit gracilis muscle as an animal model. The ipsilateral saphenous nerve (sensory) was transferred to the motor nerve of the gracilis muscle for sensory neurotization. A 4 x 4-cm2 area of skin island over the midportion of the gracilis muscle was harvested as a full-thickness skin graft. The upper half of the gracilis muscle was then excised, becoming a rough surface. The harvested skin was reapplied on the trimmed rough surface of the muscle. After 6 months, retrograde and antegrade horseradish peroxidase labeling studies were performed through skin and muscle injection. The group with a free skin graft was compared with the group with an intact surface of the gracilis muscle. This study clearly shows that sensory nerves can regenerate and penetrate into the trimmed muscle surface and grow into the overlying grafted skin. However, if the muscle surface is intact as with the compared group, sensory reinnervation of the grafted skin is not possible.     

The SOOF lift: its role in correcting midfacial and lower facial asymmetry in patients with partial facial palsy

Subperiosteal face lifting has gained wide acceptance in aesthetic surgical practice. It may also have a role to play in patients with partial facial palsy. These patients demonstrate poor static position of the mouth but maintain some degree of facial movement. This study examined the role of subperiosteal facial suspension as an alternative treatment modality in this patient group. In this series, five patients with varying degrees of partial facial palsy underwent subperiosteal face lifting, including sub-orbicularis oculi fat elevation via a temporal, lower lid, and buccal approach, thereby mobilizing and elevating and suspending the zygomaticus major and levator labii superioris muscles on the facial skeleton. An attempt was made to categorize the patients according to overall House-Brackmann score. It was not possible to precisely classify the patients by this method, although the approximate scores were two patients scoring 3, two patients scoring 4, and one patient scoring 5. To overcome inconsistencies with this method, the degree of static and dynamic asymmetry of the mouth and also the excursion of the mouth were graded separately. Four patients with mild to moderate dynamic and static asymmetry (House-Brackmann score of approximately 3 and 4) who maintained excellent or good excursion of the mouth achieved excellent or good results. One patient with poor excursion and severe partial facial palsy (House-Brackmann score of 5) was improved but remained markedly asymmetric (follow-up, 4 months to 1 year). Subperiosteal face lifting is a useful therapeutic modality for management of selected patients with mild partial facial palsy. These patients demonstrate asymmetric static position but maintain some degree of muscle excursion. Patients with severe facial palsies with poor muscle excursion continue to require muscle transfer or sling procedures. The authors hope that long-term follow-up will confirm the sustained effect of midfacial suspension in this selected patient group.     

Criteria of the homology and phylogeny of facial muscles in primates including man. I. Prosimia and Platyrrhina]

The facial muscles of primates are derivates of sphincter colli profundus muscle and platysma myoides. A third superficial muscle layer which is present in primitive mammals is found as a rest in Tupaiiformes. The facial muscles of some Lemuriformes must be considered as a model from which originate the facial musculature of other primates. The new formation of muscles takes place at the margine of the original muscle layers; marginal muscle fibers assume another run and get individualized. So it can be seen in facial muscles of prosimians and platyrrhine monkeys that the profound muscles of mouth and nose and some of the rostral margine of the auricle have orginated from sphincter colli muscle, all others from platysma myoides. Primitive and modified muscle forms and intermediate muscle forms can be observed among prosimians as well as among platyrrhine monkeys and by this it is possible to see the homology of the facial muscles.     

Anatomical partitioning of three multiarticular human muscles.

To examine neuromuscular partitioning within human muscles, the innervation patterns and muscle fiber architecture of the flexor carpi radialis (FCR), extensor carpi radialis longus (ECRL) and lateral gastrocnemius (LG) muscles were examined. Consistent patterns of innervation between specimens were found within each of the three muscles. The nerve to the FCR clearly innervates three major architectural divisions of the muscle. The ECRL is innervated by two different muscle nerves. Branches of these nerves innervate at least two distinct anatomical subvolumes. However, the subvolumes of the ECRL defined by muscle architecture are not totally congruent with those defined by the innervation pattern. In the LG, the single muscle nerve branches into two main divisions, and these subsequently divide into branches which supply the three heads. However, each head does not receive a completely private nerve. These results indicate that human muscles are partitioned in a manner roughly similar to the divisions of the same muscles in cats and rats, but with less congruency of architecture and innervation.     

Morphology and relationships of the orangutan fatty cheek pads

The present paper examines the anatomical relationships as well as possible developmental and functional relationships of the fatty cheek pad characteristic of the adult male orangutan. The research involves the dissection of 11 orangutans of both sexes in a variety of age categories. All specimens possess either a fat pad or a subcutaneous connective tissue fascial compartment in the lateral face extending superiorly from slightly above the inferior border of the mandible to the temporal region. In immature specimens as well as adult females, fat deposits within the connective tissue compartment are scarce or nonexistent, whereas pubescent male specimens or older possess accumulations of fibro-fatty tissues in this region. The extensive fat accumulations of the adult male cheek flange are related to age and sex and to modifications in related facial musculature, especially mm. platysma, zygomaticus, orbicularis oculi, and orbitotemporalis and frontalis. These muscles are clearly related to the cheek pad structures in both sexes but appear to assume a supportive role in the males. The cheek pad has no direct bony attachments, but its mass may have a significant effect on facial morphology. The development of the cheek pad is temporally variable and its function remains speculative although the presence of a fully developed flange may be related to behavioral modifications.     

Incomplete normalization of dog gracilis muscle grafts with neurovascular repair despite long-term recovery.

Skeletal muscle grafts performed with neurovascular repair are used extensively in clinical situations. However, most controlled experimental studies on the efficacy of such grafts have been conducted on muscles with a relatively small mass and over a limited recovery period. Therefore, selected cellular and matrix component properties of the comparatively large dog gracilis muscle (75 g) were studied 9-12 mo after orthotopic neurovascular grafting. The grafted muscle wet weights were 71% of the contralateral control (sham-operated) muscles. In addition, the concentrations of noncollagenous protein (13%), DNA (28%), and RNA (34%) were significantly reduced in the grafts. However, the concentration of collagen was significantly higher (41%) in the grafts. In this regard, the type III collagen phenotype showed the greatest relative increase. There was no difference between the grafted and control proteoglycan concentration. The metabolic profiles of the grafted muscles were significantly different from control. The activities of myofibrillar adenosinetriphosphatase (34%) and alpha-glycerophosphate dehydrogenase (25%) were reduced, whereas citrate synthase remained unchanged. These data suggest that recovery of up to 1 yr was insufficient for the normalization of several connective tissue matrix components and biochemical properties of the grafts.